| Message ID | 1482375688-20872-1-git-send-email-arei.gonglei@huawei.com |
|---|---|
| State | New |
| Headers | show |
Hi Michael, Ping... Regards, -Gonglei > -----Original Message----- > From: Gonglei (Arei) > Sent: Thursday, December 22, 2016 11:01 AM > To: qemu-devel@nongnu.org > Cc: mst@redhat.com; Gonglei (Arei) > Subject: [PATCH v3] virtio-crypto: zeroize the key material before free > > Common practice with sensitive information (key material, passwords, > etc). Prevents sensitive information from being exposed by accident later in > coredumps, memory disclosure bugs when heap memory is reused, etc. > > Sensitive information is sometimes also held in mlocked pages to prevent > it being swapped to disk but that's not being done here. > > Let's zeroize the memory of CryptoDevBackendSymOpInfo structure pointed > for key material security. > > [Thanks to Stefan for help with crafting the commit message] > > Signed-off-by: Gonglei <arei.gonglei@huawei.com> > Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> > Reviewed-by: Eric Blake <eblake@redhat.com> > --- > v3: > - rework the commit message [Eric] > - add Eric's R-by tag. > > hw/virtio/virtio-crypto.c | 13 ++++++++++++- > 1 file changed, 12 insertions(+), 1 deletion(-) > > diff --git a/hw/virtio/virtio-crypto.c b/hw/virtio/virtio-crypto.c > index 4f11fee..48288e8 100644 > --- a/hw/virtio/virtio-crypto.c > +++ b/hw/virtio/virtio-crypto.c > @@ -337,7 +337,18 @@ static void > virtio_crypto_free_request(VirtIOCryptoReq *req) > { > if (req) { > if (req->flags == CRYPTODEV_BACKEND_ALG_SYM) { > - g_free(req->u.sym_op_info); > + size_t max_len; > + CryptoDevBackendSymOpInfo *op_info = req->u.sym_op_info; > + > + max_len = op_info->iv_len + > + op_info->aad_len + > + op_info->src_len + > + op_info->dst_len + > + op_info->digest_result_len; > + > + /* Zeroize and free request data structure */ > + memset(op_info, 0, sizeof(*op_info) + max_len); > + g_free(op_info); > } > g_free(req); > } > -- > 1.8.3.1 >
diff --git a/hw/virtio/virtio-crypto.c b/hw/virtio/virtio-crypto.c index 4f11fee..48288e8 100644 --- a/hw/virtio/virtio-crypto.c +++ b/hw/virtio/virtio-crypto.c @@ -337,7 +337,18 @@ static void virtio_crypto_free_request(VirtIOCryptoReq *req) { if (req) { if (req->flags == CRYPTODEV_BACKEND_ALG_SYM) { - g_free(req->u.sym_op_info); + size_t max_len; + CryptoDevBackendSymOpInfo *op_info = req->u.sym_op_info; + + max_len = op_info->iv_len + + op_info->aad_len + + op_info->src_len + + op_info->dst_len + + op_info->digest_result_len; + + /* Zeroize and free request data structure */ + memset(op_info, 0, sizeof(*op_info) + max_len); + g_free(op_info); } g_free(req); }